Morphological and Functional Outcomes in the Long-Term Natural Course of Peripapillary Pachychoroid Syndrome.

Introduction: This study investigated the long-term natural history of peripapillary pachychoroid syndrome (PPS), analyzing both morphological and functional outcomes.

Methods: This retrospective study included 24 eyes from 14 participants diagnosed with PPS. No interventions were administered. Baseline and follow-up assessments comprised best-corrected visual acuity (BCVA), measured on the LogMAR scale, inner nasal (IN) and outer nasal (ON) macular thickness measured using the ETDRS (Early Treatment Diabetic Retinopathy Study) subfields. To account for repeated measures and the hierarchical structure of eyes nested within participants, and to appropriately handle incomplete longitudinal data, linear mixed-effects models were utilized for all statistical analyses.

Results: The mean age was 74 ± 7 years, and 71% of patients had bilateral PPS. All patients had peripapillary atrophy at baseline. The mean baseline BCVA was 0.05 and showed only small variations over time. ON macular thickness showed a significant decrease at 2 years (Δ = - 36.9 µm, p = 0.034), whereas IN macular thickness decreased significantly at both 2 years (Δ = - 40.75 µm, p = 0.023) and 3 years (Δ = - 39.97 µm, p = 0.042). One-quarter of participants developed a serous pigment epithelium detachment with subretinal fluid, suggesting an overlapping PPS/CSC (central serous chorioretinopathy) phenotype.

Conclusions: Peripapillary atrophy appears to be an important anatomical predisposition for PPS. Waxing and waning of intraretinal fluid were observed during the natural course of PPS, with a significant reduction at 2 years. Most patients remained asymptomatic and maintained stable BCVA throughout long-term follow-up, indicating a generally favorable prognosis in the absence of intervention.